Responsible Lawn Management in the Era of Climate Change

Responsible Lawn Management in the Era of Climate Change

  • By Ralph Morini
  • /
  • September 2019-Vol.5, No.9
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  • 2 Comments

The perfect turfgrass lawn represents the desired, and in some cases required, external appearance for many of our personal and commercial properties. In fact, it appears that lawns are the largest irrigated crop in the country, covering an area of over 63,000 square miles. But around the country, and perhaps especially for us in the transition zone, where neither cool nor warm weather turf grasses thrive without extensive, expensive and potentially polluting assistance, it makes sense to rethink our approach to lawn management.

For those who, for whatever reason, are committed to turfgrass lawns, this article reviews best grass choices and practices for cultivating lawns in the Virginia Piedmont. The second part presents environmentally friendlier alternatives to turfgrass monocultures that can save time and money, reduce chemical use and carbon footprint while maintaining an attractive landscape with many offsetting benefits.

Best options for a turfgrass lawn

Turfgrass lawns are appreciated for their color, appearance, soil stabilization and resilience. Their downsides are many, however, especially in our region where all varieties struggle at some point in the year with our environmental conditions. Cool weather varieties need help to stay green and healthy during our hot dry summers. Warm weather grasses have 3-5 month dormant periods during our relatively cold winters. Nevertheless, if we narrow grass choices to a few ‘best performers” we can optimize chances of success while minimizing the negatives.

Cool Weather Turfgrass Options

Cool weather grasses prefer temperatures in the 60-75° range. They are active early spring through early summer and late summer through early winter. Growth slows in the summer heat. They can be planted in spring, but fall planting provides a longer period to become established before summer heat arrives. Recommended choices are:

  • Tall Fescue
    • Germinates in 10-14 days
    • Full sun to moderate shade
    • 2-3” cut height
    • Develops deep roots, yielding low- to- moderate maintenance requirements
    • Requires 2-4 lbs of nitrogen/1000 square feet per year
  • Kentucky Bluegrass
    • Germinates in 14-21 days. Slow to establish, best to plant in fall.
    • Likes full sun
    • 1.5-2.5” cut height
    • May go dormant during extended heat or drought (turns brown, but will come back)
    • Has an aggressive creeping growth via rhizome, can build thatch
    • Requires 3-4 lbs of nitrogen per 1000 square feet per year
  • Fine leaf fescue
    • Germinates in 10-14 days, establishes slowly, preferring fall planting
    • Shade tolerant. Handles dry, poor soils. No wet soils. Best in low traffic situations.
    • Fine leaf texture objectionable to some
    • 1.5-2.5” cut height
    • Low fertilization needs, 1-2 lbs nitrogen per 1000 square feet per year
  • Perennial Ryegrass
    • Germinates 7-10 days, establishes quickly
    • Full sun to moderate shade. Good wear resistance, poor heat and drought tolerance. In our area, successful in cooler areas above 1500 feet elevation
    • Often mixed with 10-20% Kentucky bluegrass to get quick establishment with the longer term creeping spread of the bluegrass
    • Low mowing heights, 1-2.5”
    • Likes 2-4 lbs nitrogen per 1000 square feet per year.

A Tall Fescue and Kentucky Bluegrass blend is attractive for the greater Piedmont area, offering the benefits of diversity and complementary characteristics, even though the look is less uniform than a single variety would be.

Warm weather grasses for the VA Piedmont

Warm weather grasses thrive in temperatures in the 80-95° range. They go dormant for 3-5 months during the winter, depending on location and temperature. They typically have fewer pest problems, lower water requirements and are less sensitive to summer extremes than the cool weather types. Best time to establish them is from mid-May through June.

Bermudagrass sod: Photo: Bermudaattractions.com

  • Bermudagrass
    • Fast growing via stolons and rhizomes; can invade beds; may require thatch management
    • Resilient when damaged
    • Full sun; poor shade tolerance
    • .5-2.5” cut height. When cutting below an inch, use a reel mower.
    • Likes 2-4 lbs nitrogen per 1000 square feet per year
  • Zoysiagrass
    • Slower grower than bermudagrass, more cold tolerant with a shorter dormant period
    • Grows via stolons and rhizomes, dense habit helps choke out weeds
    • Low maintenance, less mowing
    • 1-2.5” cut height, requires a sharp mower blade
    • 1-2 lbs nitrogen per 1000 square feet per year.

Best Practices

To minimize the negatives of lawn management, follow these principles:

  • Test soil every 3 years. Follow pH and nutrient recommendations. Too much nitrogen fertilization, a common tendency, increases the chance of leaching and pollution and focuses plants on leaf rather than root growth.
  • For new lawns, till soil 4-6 inches deep. If adding lime, add prior to tilling and mix it into the soil.
  • For patching or interseeding, loosen soil with a core aerator or vertical mower (dethatcher) prior to planting. Don’t pulverize, small clumps are ok.
  • Starter fertilizers should be high in phosphorus, rather than nitrogen. NPK (Nitrogen, Phosphorus, Potassium) ratios of 1:2:1 or 1:2:2 are appropriate.
  • When choosing seed, look for endophyte enhanced products. Endophytes are a beneficial fungus that can be found in tall fescue and ryegrass seeds and increase disease and pest resistance.
  • Water lightly but frequently until germination, more thoroughly as root systems develop.
  • Pay attention to the grass’s preferred cut height range. Keep the mower blade sharp and balanced. Don’t remove more than 1/3 of the grass blade length per cut.
  • Choose fertilizers with a mix of fast and slow release nitrogen. They provide N for immediate use while continuing to release nutrients throughout the season. Slow release (water insoluble nitrogen or WIN) may be chemically or microbially intitiated and is less likely to leach than water soluble chemical products. Microbial decomposition brings the benefit of feeding the soil and building a healthier soil organism population.
  • Plug aeration reduces compaction while aerating lawns. Do it after germination in the spring but before summer heat or preferably in the fall when surface disruption is less objectionable.
  • Thatch, which builds when dead plant material builds faster than it decomposes, is an issue when it is a ½” or more thick. It is most common in grasses that grow via rhizome and stolon. Kentucky Bluegrass and Bermudagrass are prone to thatch build, especially if heavily fertilized. Vertical mowing does a good job of removing it.

Fertilization Tips

Leaching of fertilizers and lawn chemicals is a significant environmental problem linked to turfgrass lawns. To get the benefit of the use of these products while minimizing negative impacts:

  • Follow soil test guidance carefully.
  • Select slow release nitrogen fertilizers which are less likely to leach and less likely to provide too much nitrogen at one time.
  • If following a chemical manufacturer’s multi-step lawn management program, be aware that they tend toward heavy nitrogen additions. Manage quantities carefully.
  • Calibrate your spreaders so that you know how much chemical you are adding.
  • Return clippings to the lawn. This is best done with a mulching mower which reduces clipping size and gets them to ground level where they decompose and reduce fertilization needs by up to 1/3 of the annual requirement.

Weed Management

Weeds are a perpetual issue for turfgrass lawns. No matter how well controlled, they will continue to reappear year after year. Nevertheless, there are best management practices for weed management:

  • Identify the weed(s). Select herbicides targeted to the type and variety of weeds in question. Apply them when they will be absorbed by the plant.
    • Winter broadleaf weeds including henbit, dead nettle, chickweed, sebara, bittercress and geranium germinate in late fall, flower in the spring and are best controlled in fall or warm winter periods before flowering and seed set.
    • Perrenial broadleafs like dandelion, clover and plantains should be treated in spring during their rapid growth period where absorption is high.
  • Be sure your selected herbicide is appropriate for the type of grass in the lawn. Read the complete label and follow directions.
  • If using a weed and feed product, select one with a high proportion of slow release nitrogen.
  • If using a pre-emergent herbicide to treat crabgrass and summer annual weeds, apply between the forsythia/daffodil bloom and dogwood bloom periods. If using corn gluten meal, an organic pre-emergent, note that it adds about 1 pound of nitrogen per 1000 sq. ft. Other N applications should be reduced accordingly. Note also that in trials at VA Tech, corn gluten meal, while environmentally friendlier than chemicals, is about 60% as effective in weed control. Don’t aerate after pre-emergent application or the weed barrier will be damaged.

The Mixed Lawn Alternative 

Best turfgrass management practices aside, the impacts of climate change, pollution, monocultures and pollinator decline are changing the way we look at lawn management. The legitimate goals of reducing chemical use, providing a more receptive pollinator environment, and adding diversity to our home ecosystems are spawning a movement away from the perfect turfgrass lawn.

The strength of turfgrass is that it handles traffic better than alternative lawns. Its future looks secure for sports fields and high traffic areas. Beyond these havens however, there is a definite trend to augment turfgrass with a varied plant mix. Many native weeds are more deeply rooted which helps them stay greener during hot, dry periods. In addition, their low height habits significantly reduce mowing requirements over the course of the growing season. Weeds like white clover were included in seed mixes prior to the 1950s. They fix nitrogen in soils, feeding turf grasses, reducing fertilization requirements, and their flowers provide pollen and nectar for pollinators. What mixed lawns give up in uniformity, they make up for in diversity and environmental friendliness.

Reducing Lawn Area

Wildflower meadow: Photo: Kristine Paulus

A growing trend to make properties more climate friendly is to reduce lawn area, replacing it with vegetable beds, shrubs, native perennial gardens, rain gardens, wildflower meadows and habitat gardens. It makes sense to maintain turfgrass in high traffic areas while partially replacing it to create climate-friendly features. Even in neighborhoods where uniform lawns are valued property elements, there are ways to reduce the monoculture and its associated negatives.  For more about meadow gardens, check out this 2017 Garden Shed article: “Meadow Gardening,” https://piedmontmastergardeners.org/article/meadow-gardening/.  Looking for ideas on lawn alternatives?  Take a look at “Alternative Lawns, https://piedmontmastergardeners.org/article/alternative-lawns/.

Grass removal is probably the hardest part of any conversion to a smaller lawn. Common techniques include:

  • Physical removal: Using hand tools to dig or scrape up sod is practical for smaller spaces. Sod can be composted for later use. Roto-tillers are a good option that can work the grass into the soil for decomposition. Loosening the top 4-6 inches of soil will help new plants get a root system established.
  • Solarizing: Covering the area with sheet plastic, held down around the edges by boards, rocks, bricks or anything heavy, for about 6 weeks in summer will kill grasses and enable easier cultivation for the planned changes. Adding some compost after plastic removal will help rebuild soil organisms killed by the solarization process.
  • Non-selective herbicides, like glyphosate are a last resort where there is no practical alternative. If this is your choice, follow directions carefully for your and the environment’s protection.

Our Mower Brakes for Pollinators

Author’s mixed plant, reduced area lawn in August

A few years ago, after moving to a house where the prior owner had valiantly but vainly tried to maintain a turfgrass lawn, we decided to promote mixed lawn plantings while reducing lawn area a little bit each year. We’re happy with the appearance and actually enjoy seeing the pollinators frequenting everything from winter weeds to the clover we’ve added to the lawn. We’ve reduced lawn area, replacing it with low maintenance plantings of various types and added non-lawn planting features every year. We use no lawn chemicals, water only the vegetable beds and containers (with most water coming from rain barrels), and mow only when it’s needed. Future plans are to continue reducing lawn, focusing more on native plants. The photo shows the lawn in August during a hot dry summer, still looking pretty presentable.

Honestly, this article started out to describe chemical-free turfgrass lawn care. But it quickly became apparent that for turfgrass lawns, chemical-free isn’t going to work. Thus, I’ve  explained how to minimize the negatives for those committed to that. With all due respect to turfgrassers, the world is moving on. Like so many things, the perfect lawn is becoming more a relic of the past than a staple of the future.

As individuals, it sometimes seems like our impact on climate change is inconsequential, but there is strength in numbers. As more of us move in a climate-responsible direction, we will affect everything from neighborhood values to the lawn care products available, and ultimately, public policy. Why not be part of a climate-responsible future. After all, beauty is in the eye of the beholder.

Sources:

“More Lawns than Irrigated Corn,” NASA Earth Observatory, (2005) https://earthobservatory.nasa.gov/features/Lawn/lawn2.php

“The Lawn Is the Largest Irrigated Crop in the USA,” https://geog.ucsb.edu/the-lawn-is-the-largest-irrigated-crop-in-the-usa/, University of California at Santa Barbara Dept. of Geography

“What Grass Should I Grow for My Lawn,” Dr Mike Goatley, Extension Turfgrass Specialist, VA Tech, https://www.sites.ext.vt.edu/newsletter-archive/cses/2008-03/WhatGrass.html

“Fall Lawn Care,” Va.Cooperative Extension https://www.pubs.ext.vt.edu/content/dam/pubs_ext_vt_edu/430/430-520/430-520-pdf.pdf

“Spring and Summer Lawn Management for Cool Season Turgrasses,” Va. Cooperative Extension,

https://www.pubs.ext.vt.edu/content/dam/pubs_ext_vt_edu/430/430-532/430-532_pdf.pdf

“Reducing Pesticide Use in the Home Lawn and Garden,” Va. Cooperative Extension, https://www.pubs.ext.vt.edu/content/dam/pubs_ext_vt_edu/450/450-725/450-725.pdf

 

Weedalert.com (weed identification), https://www.weedalert.com/search-by-region-results.php?region=4

“Lawn Alternatives,” Home and Garden Information Center, U of MD Extension, https://extension.umd.edu/hgic/topics/lawn-alternatives

“Turfgrass Frustration in Central Virginia,” by Cathy Caldwell, The Garden Shed, September 2018, https://piedmontmastergardeners.org/article/turfgrass-frustration-in-central-virginia/

 

2 Comments

  1. Dell Erwin

    Turf is so bad for the environment! Requires watering, fertilizer, herbicides, mowing (adding pollution, using fossil fuels/electricity) and wastes time, which can be better spent in other types of gardening . I wish you would not present turf as inevitable. Please present the harm to our environment and responsible solutions., which I think is a moral duty, especially for master gardeners. Thanks for your consideration.

  2. Ralph Morini

    Hello Dell.
    Thanks for your comment. While I agree personally with you, our charter at The Garden Shed is to present science based gardening guidance and editorializing has to be done with care. I struggled with what to present and how to present it in the article and in the end thought a summary of best turf lawn practices, including non-turf lawn options, making my personal opinions known but saving them until the end, would be the optimal approach. My hope is that folks still desiring turfgrass lawns will keep reading rather than quit in the middle of the article and maybe move toward a more natural approach. I guess time will tell.

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